I've got a C-8 wide angle lens for my Canon 1014xl-s but I've become interested in playing with fisheye lens effects. My preference is for a circular image rather than full frame. A quick search of eBay leads to some cheap Asian fisheye/macro screw on lenses built for digital cameras. Like this one:

I suspect it will not give a true fisheye effect but they are cheap enough to start with and if there is a bit of distortion then I will be happy with that. A suppose another option would be to get screw on lens for something like 52mm and a step up ring and I can get a circular image.

For super 8 cameras with interchangeable lenses, there is a 1.9mm fisheye lens available. It was mentioned in "The Book of Movie Photography" - an English publication from the early 80s. I can't remember which company produced this lens but it was a German sounding name that began with a 'K.' I have no idea what lens mount it had. Nevertheless, you can imagine that such an item would be super rare.

I had shot a bit of test footage with a video fisheye adapter screwed on to the front of my Canon 1014E's lens. This gave a circular fisheye image. However, there was a slight bit of softness in the images. Though it is hard to say whether this softness was due to the adapter or the fact that I was shooting on Ektachrome 7240. Unfortunately, I can't remember the brand name or any other details about the adapter as it was a few years ago when i tested it outside the shop.

Patrick wrote:For super 8 cameras with interchangeable lenses, there is a 1.9mm fisheye lens available. It was mentioned in "The Book of Movie Photography" - an English publication from the early 80s. I can't remember which company produced this lens but it was a German sounding name that began with a 'K.' I have no idea what lens mount it had.

Kinoptik has made 1.9mm C-mount lens. Century has also made 1.9mm C-mount lens.

I purchased a couple of screw-on wide angle conversion lenses and found the quality of the resulting images to be poor, with a lot of blurriness and color fringing. As has been suggsted, the best way to go wide angle in Super 8 is to get a camera that accepts interchangeable lenses.

The Kinoptik 1.9mm f/1.9 Super Tegea lens already mentioned is large and heavy, and it projects a circular image just 8.7mm in diameter. Backfocus may be an issue with this lens, too. The Century 1.9mm f/1.8 Ultra Wide Angle lens is much more compact than the Super Tegea, weighing just ten ounces. It's 2.23 inches long. Better still, unlike the Super Tegea, it covers the full regular 16mm format, giving a diagonal angle of view of 180 degrees (according to the manufacturer). Fitted to my Beaulieu 4008 ZMII, the Century lens produces an angle of view equivalent to that of the Schneider-Kreuznach UWL III conversion lens fitted to an Optivaron lens set at its 6mm focal length.

The best lens for wide angle work with Super 8, in my view, is the exceedingly rare Century 2.5mm f/1.8 Xtreme Wide Angle lens sold by Century Precision optics in the 1980s. Weighing a little more than nine ounces and 4.4 inches in length, this lens only covers Super 8, but its field of view is significantly greater than that of the Century 1.9mm Ultra Wide Angle lens on a Super 8 camera. The manufacturer claims a diagonal angle of view of 140 degrees. Century offered a 3.5mm f/1.8 Super Wide Angle lens for Super 8 as well that provided a 100 degree angle of view.